J. Org.Chem., Vol. 58, No. 3, 1978
CYANIDE IONWITH CARBONYL COMPOUNDS
481
The Reaction of Cyanide Ion with Carbonyl Compounds in Dipolar Aprotic Solvents' NORBERT A. GOECKNER AND H. R. SNYDER* Roger Adams Laboratory, University of Illinois, Urbana, Illinois 61801 Received August 1.4, MY.?? nimethylformamide solutions of 9-benzoylanthracene and sodium cyanide a t 80' give intensely blue solutions from which 9-cyanoanthracene, 9,10-dicyanoanthracene, 9,l@dihydroanthracene, anthracene, and benzoic acid can be isolated. Addition of the mild oxidizing agent sodium 9,lO-anthraquinone-1-sulfonateto the blue solutions yields as major products only 0,lO-dicyanoanthracene and benzoic acid. Similar treatment of $acetyl-, $benzoyl- , 9-chlorocarbonyl-, 9-formyl-, or 9-carbomethoxyanthracene also yields 9,lO-dicyanoanthracene. 2,3,9,10-Tetracyanoanthraceneis obtained from 9,lO-dicyanoanthracene and cyanide ion in the presence of Oxidizing agent.
The nucleophilic reactions of cyanide ion and of anions from active methylene compounds with certain aryl-substituted unsaturated hydrocarbons,2 aromatic nitrile^,^ aromatic nitro ~ o m p o u n d s , and ~ * ~ aromatic heterocyclcs3b in dipolar aprotic solvents appear to proceed via carbanionic addition products, usually formed reversibly, which by further reaction with added oxidizing agents or protonating agents or by electron exchange reactions, in which the original aromatic compound may participate, lead to a variety of products. Some of the reactions promise to be of unique value in synthesis. The initiation of the rcactions of aromatic compounds results from electron withdrawal by an activating group, nitro or nitrile, which facilitates the addition of the cyanide ion to the aromatic system. It would be expected that a carbonyl group attached to a suitable aromatic system would be less effective than a nitro or nitrile group in facilitating attack by the cyanide ion. The present work was undertaken to test the reactivity of some aromatic carbonyl compounds toward cyanide ion. I n the studies of the highly unsaturated hydrocarbons2 and the nitriles3 and nitro compounds4 the development of color when the substance being tested was mixed with sodium cyanide in an aprotic solvent was taken as an indication of attack by cyanide ion with the formation of a carbanion. When simple aromatic carbonyl compounds, such as benzophenone, benzaldehyde, and ethyl benzoate, were teqted in this way no significant color development was observed a t ambient or slightly elevated temperatures, but, when the aromatic compound was one having a ketone, ester, acid chloride, or aldehyde function attached to the 9 position of the anthracene system, such a test solution d o veloped a deep blue color, slowly a t room temperature and rapidly a t slightly elevated temperatures. Examination of mixtures in which 9-benzoylanthracene l a and sodium cyanide were allowed to react in DAIP revealed the presence of a number of products. By analogy with the reaction of the nitrile,3 the carbanion 6 would be expected to form and to generate the keto nitrile Id even if no oxidizing agent were added.
However, none of the keto nitrile was found, and a principal product isolated (23%) see Table I, expt A)
(1) Grateful acknowledgment is made to the U. S. Army Research Office ( G r a n t No. Dh-ARO(D)-G679 and G857) for the partial support of this work. ( 2 ) (a) 13. E. Galbraith and H. R. Snyder, J. Ora. Chem., 31, 380 (1907); (b) I
